147. Optional faster zig-rate.
It is my belief that convoy clocks were set to zig at a periodicity of circa 8 minutes, rather than (I gather) the 17 minutes we now have.
The difference is important. In the 17 minute scenario, there just is enough time to determine the convoy heading, speed and to fire and hit to a 15 minute TOI against a target which will maintain speed and heading.
Were the historical (8 min?) zig rate enabled (on an optional basis of course) then this attack profile would need to change completely, as now the mean-track and mean-speed would form the data for the TDC, making long range shots a bit more difficult, and a longer period of observations needed before firing. This in turn allows for more detection opportunities, especially if aircraft and/or radar arrive.
I suggest that zigs be limited to plus or minus 10-15 degrees of a base course, excepting after a hit on a merchantman or detection of a u-boat, whereafter the convoy can change by 30 degrees relative to the base course, with 15 degrees for the 2nd zig 8 minutes later, before reverting back to the original base course at a rate of 5, 10, 15 degrees per following 8 minute zig. Once back on the base course, the maximum zig would return to 15 degrees in either direction?
This optional change would greatly benefit navigators, as now they'd need to accurately plot the position of a boat at two recorded times, then derive the convoy speed from that. Similarly establishing the 1st and 2nd AOB's (and therefore headings) of the convoy, and the time they changed, to establish the mean-course.....
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